The invention relates to a cable device for actuating a control element, in particular for actuating the shift shaft of a motor vehicle transmission.
European Patent No. EP 0 437 509 B1 discloses a cable device for operating a control element, to be precise for operating a parking brake of a vehicle. The cable device has a core and a sheath encasing the core. The core is configured, as a continuous wire, the two ends of the core being connected to the ends of the actuating levers of two parking brakes. At an abutment, a controlling device is provided, which is configured in such a way that at least a part of the sheath is moveable. The result is that the core and the sheath at least partly form a pull-push cable. When the parking brake or parking brakes of the motor vehicle is or are to be actuated, the movable part of the sheath is displaced by the controlling device, in such a way that the core exerts a pulling force, so that the actuating levers of the parking brakes are then accordingly actuated.
German Published, Non-Prosecuted Patent Application No. DE 197 42 573 A1 discloses a cable device, in which a manual transmission or an automatic transmission of a motor vehicle is actuated via a cable device. For this purpose, the core of the pull-push cable, which is formed from the core and from the sheath, is operatively connected to a manual shift lever. The sheath is arranged so as to be at least partly movable. An adjusting element is provided, with the aid of which a change in length of the sheath can be carried out, so that the cable device can be optimally adjusted.
The cable device disclosed in European Patent No. EP 0 437 509 B1 is not configured optimally. This conventional cable device is configured to be electrically actuable, and has an electric motor and corresponding nuts or a gearing. The resulting controlling device for moving the sheath functions in dependence of the electric current which is available during normal operating conditions. A problem arises when the electric power supply or an electronic system of the motor vehicle fails or the battery of the motor vehicle is no longer operational. In this case, the parking brakes, once set and locking the wheels of the motor vehicle, can no longer be easily released, since, when the controlling device is in a currentless state, the controlling device cannot easily be unlocked. Experience has shown that, particularly in winter months when the batteries of motor vehicles partially lose their operating capacity, the parking brakes of motor vehicles of this kind cannot always be released readily through the use of these conventional cable devices. Towing such a vehicle whose parking brake cannot be released is consequently either impossible or at least very difficult. In summary, an absolute operating reliability of the conventional cable device cannot be ensured in the event of a failure of the controlling device or in the event of a failure of the electric power supply of the motor vehicle.
It is accordingly an object of the invention to provide a cable device which overcomes the above-mentioned disadvantages of the heretofore-known cable devices of this general type and which has an increased operating reliability, in particular such that the control element to be actuated can at least be unlocked in the event of a failure of the controlling device on account of a lack of electric power.
With the foregoing and other objects in view there is provided, in accordance with the invention, a cable device, including:
a core having a first end region and a second end region;
a control element operatively connected to the first end region of the core;
an abutment;
a controlling device disposed at the abutment;
a sheath substantially encasing the core, the sheath having a first region and a second region;
the first region of the sheath being fixedly mounted, the second region of the sheath being movably mounted such that the sheath is at least partly movable by the controlling device and such that the core and the sheath form a pull-push cable; and
an emergency actuation device operatively connected to the core and configured such that, in an event of a functional failure of the controlling device, the control element can be actuated, via the core, by the emergency actuation device.
In other words, the object of the invention is achieved by a cable device for actuating a control element, in particular for actuating the transmission shift shaft or selector shaft of a motor vehicle transmission, preferably the parking lock of the transmission that is engageable and disengageable with the aid of the cable device, with at least one core and with a sheath substantially encasing the core, a first end of the sheath being fastened, and the sheath, preferably the second end of the sheath, being mounted so as to be at least partly movable via a controlling device disposed in the region of an abutment, so that the core and the sheath form a pull-push cable, and a first end of the core being operatively connected to the control element, in particular the transmission shift shaft, wherein an emergency actuation device is provided, and the emergency actuation device is configured to cooperate functionally with the core in such a way that, in the event of a functional failure of the controlling device, the control element can be actuated with the aid of the core via the emergency actuation device.
Since, in addition to the controlling device, an emergency actuation device is provided, which can be actuated by hand operation, i.e. manually, in such a way that, in the event of a functional failure of the controlling device, the control element, in particular the shift shaft or the parking brake, can be actuated, the disadvantages described above are avoided. Even in the event of a failure or interruption of the electric power supply of the motor vehicle or a failure of the electronic system of the motor vehicle, the parking brake can be released or the parking brake engaged in the transmission can be disengaged via the cable device. The operating capacity or operating reliability of the cable device is thereby increased.
According to another feature of the invention, the emergency actuation device has a release element with a shackle operatively connected to the second end region of the core.
According to yet another feature of the invention, the emergency actuation device includes a release element operatively connected to the second end region of the core, wherein the release element is secured with the fastening element.
According to a further feature of the invention, the fastening element has first limbs and second limbs, the release element has an outer region, the first region of the sheath is an end region of the sheath, and the first limbs engage the end region of the sheath and the second limbs surround the outer region of the release element.
According to yet a further feature of the invention, the emergency actuation device is configured to be mounted on a vehicle console.
According to another feature of the invention, the controlling device includes an electric motor, a gearwheel stage and an actuating nut.
According to yet another feature of the invention, the actuating nut is disposed within the abutment, the sheath has a region with an external thread, and the actuating nut engages the external thread.
According to a further feature of the invention, the second region of the sheath is an end region of the sheath, and the controlling device is configured to displace the end region of the sheath.
According to yet a further feature of the invention, the control element is a transmission shift shaft, an actuating lever is operatively connected to the transmission shift shaft, and an actuating rod connects the first end region of the core operatively to the actuating lever.
According to another feature of the invention, the actuating rod is at least partly in engagement with a ball-mounted actuating arm.
According to yet another feature of the invention, the control element is a transmission shift shaft configured to be put in a plurality of selector stages including a parking lock stage, the controlling device includes an electric motor, and the electric motor is switched to be currentless in all selector stages except in the parking lock stage.
According to a further feature of the invention, the first region of the sheath is a first end region of the sheath and the second region of the sheath is a second end region of the sheath.
According to yet a further feature of the invention, the control element is a motor vehicle transmission shift shaft, and the controlling device actuates the motor vehicle transmission shift shaft.
According to yet another feature of the invention, the controlling device actuates the motor vehicle transmission shift shaft such that the controlling device selectively engages and disengages a parking lock.
According to yet a further feature of the invention, the second region of the sheath is an end region of the sheath, and the end region of the sheath is mounted at the abutment.
With the objects of the invention in view there is also provided, in combination with a vehicle transmission having a transmission shift shaft, a cable device which includes:
a core having a first end region and a second-end region;
the first end region of the core being operatively connected to the transmission shift shaft;
an abutment;
a controlling device disposed at the abutment;
a sheath substantially encasing the core, the sheath having a first end region and a second end region;
the first end region of the sheath being fixedly mounted, the second end region of the sheath being movably mounted such that the sheath is at least partly movable by the controlling device and such that the cable device forms a pull-push cable; and
an emergency actuation device operatively connected to the core and configured such that, in an event of a functional failure of the controlling device, the transmission shift shaft can be actuated, via the core, by the emergency actuation device.
Other features which are considered as characteristic for the invention are set forth in the appended claims.
Although the invention is illustrated and described herein as embodied in a cable device for actuating a control element, it is nevertheless not intended to be limited to the details shown, since various modifications and structural changes may be made therein without departing from the spirit of the invention and within the scope and range of equivalents of the claims.
The construction and method of operation of the invention, however, together with additional objects and advantages thereof will be best understood from the following description of specific embodiments when read in connection with the accompanying drawing.